Lockstitch shoe sewing machines



Dec. 13, 1955 H. E. ELLIOTT ET AL 2,726,610

LOCKSTITCH SHOE SEWING MACHINES Filed March 7, 1952 6 Sheets-Sheet 1[hi/anions Harold E Elliott Stanley E Edmptorz By their Attorney Dec.13, 1955 H. E. ELLIOTT ETAL LOCKSTITCH SHOE SEWING MACHINES 6Sheets-Sheet 2 Filed March 7, 1952 Inv e nzong Harold E. Ellioiz n ma mmZ 5A 9 F e 2 i Dec. 13, 1955 H. E. ELLIOTT ETAL 2,726,610

LOCKSTITCH SHOE SEWING MACHINES Filed March 7, 1952 6 Sheets-Sheet 3Inventors Harold E. E'Zlz'ozfi zanley E F'ramp ion y heir/1L for]? Dec.13, 1955 H. E. ELLIOTT EFAL 2,726,610

LOCKSTITCH SHOE SEWING MACHINES Filed March 7, 1952 6 Sheets-Sheet 4Inventors HarolaE Elliott Stanley E. Hampton By their Attorney Dec. 13,1955 H. E. ELLIOTT ETAL LOCKSTITCH SHOE SEWING MACHINES 6 Sheets-Sheet 5Filed March 7, 1952 [In/en tors" Harold E Elliott Sta nley E Hampton ByZ/zezr Attorney Dec. 13, 1955 H. E. ELLIOTT ET AL 2,726,610

LOCKSTITCH SHOE SEWING MACHINES Filed March 7, 1952 6 Sheets-Sheet 6Laop Shrew/er [04 (/brwara'X rearward) A Loop Ref/acting Arm [[2 4/(zransverse) .Tfzre ad Case Rezal'm'n AlemberJZ 9 Three a Casejfezainz'ly Member 5' Inventors Harold E Elliott Stanley 5' Frampzon Bytheir Attorney United States Patent LOCKSTITCH snon SEWING MACHINESHarold Ernest Elliott and Stanley Ernest Frampton,

Leicester, England, assignors to United Shoe Machinery Corporation,Flemington, N. J., a corporation of New Jersey Application March 7,1952, Serial No. 275,318

Claims priority, application Great Britain March 22, 1951 14 Claims.(Cl. 11238) The present invention relates to improvements in curved hookneedle shoe outsole sewing machines in which there is a horizontal worksupport and a shuttle above the work support and more particularly to animproved loop taker and spreader arrangement for a sewing machine of thetype disclosed in United States Letters Patent No. 2,056,670, grantedOctober 6, 1936, upon application of J. Gouldbourn et al.

In the design of a curved hook needle lockstitch shoe sewing machine ofthe type indicated, it has long been recognized that for the bestresults in handling the threads going to make up a lockstitch seam, theuse of a true shuttle which passes entirely through each loop of thread,has many advantages over the use of a loop taker type shuttle whichmerely carries each loop of thread about a thread supply case withoutitself passing through the loop. From a mechanical point of viewhowever, the loop taker type of shuttle has advantages over the trueshuttle particularly because a true shuttle requires a separate driverhaving a lost motion gap through which each loop of needle thread mustpass as it is carried about the shuttle itself. This lost motion gap isnot only a source of noise and undue wear on the shuttle drivingconnections when operated at high speeds but it also renders the problemof timing in the machine more difficult as a result of uncertainty inthe position of the shuttle throughout the extent of the lost motiongap. Furthermore, a true shuttle requires a supporting raceway orbearing separate from the driver whereas the loop taker type of shuttlemay be secured rigidly upon a shaft of suflicient length and diameter toinsure proper rigid bearing support.

The design of the curved hook needle machine presents additionaldifiiculties for the reason that each loop of thread carried through theWork by the needle after being entered by a beak on the shuttle must bedisengaged from the hook of the needle without subjecting the thread inthe loop to the possibility of injury against the edges of the needlehook, the hook being of necessity formed with sharp edges overlying itsthread carrying throat.

' In both true shuttle and loop taker type shuttle machines where adesign is intended for high speed operation, the best mechanicalconstruction calls for a shuttle shaped in the form of a hollow cup withan internal raceway about its circumferential side walls in which alocking thread supply case is rotatably mounted, the thread case beingretained against rotation with the shuttle to assist the separation ofthe sides of each needle loop as it is passed about the thread case. Forthis purpose the usual arrangement is to provide a discontinuous flangeon the thread case surrounded by the raceway of the shuttle, one side ofa loop of thread being engaged by one end of the ange on the thread caseto prevent its rotation with t e shuttle while, the other side of theloop iscarried by the shuttle about thethread case, imparting tothe1oopia'180f twist. An example er ashuttle with such thread case isdisclosed in United States Letters Patent No. 2,208,999 granted July'23, 1940, upon application of .W. T. Minett.

In the machine of the Minett patent a loop taker type shuttle isprovided having an internally supported thread case in which the beak ofthe shuttle rotates in a plane extending entirely clear of the circularpath defined by the curved hook needle. By mounting the shuttle andthread case in this manner, the lower edge of the shuttle is disposed asclose as possible to the path of the needle so that a loop of thread mayreadily be transferred from the needle to the shuttle beak and, in beingcarried about the thread case, the loop of thread is drawn in adirection where it may readily be disengaged from the hook of the needlewithout danger of injuring the thread. By such arrangement, many otheradvantages also are obtained including elimination of lost motion gap inthe driving connections for the shuttle, but, because it is essential toinsure visibility and free space for manipulation of a shoe at the frontof the machine, an elongated shaft supported by bearings for the shuttleis impossible and the shuttle of that patent accordingly is supported bya relatively thin guide plate fitting a narrow external raceway in theshuttle. Also the patented shuttle is driven by connections includingbevel gear teeth formed on the shuttle itself and the angle between thethread extending from the point of needle operation to the shuttle withrespect to the plane defined by the rotary path of the shuttle beak issuch that special precautions must be taken to insure shedding of theloop from the shuttle beak after passing each needle loop about thethread case.

One of the various objects of the present invention is to provide animproved curved hook needle lockstitch sewing machine in which thebenefits, from a standpoint of handling thread, of a true shuttle areobtained without the mechanical disadvantages necessitated by the use ofa lost motion gap between the shuttle and its driving mechanism, themachine being capable of operating at speeds higher than thoseobtainable with a true shuttle machine without excessive noise or unduewear frequently occurring in a true shuttle type machine. Another objectis to provide a machine of the type referred to with a loop taker typeof shuttle in which the advantages of operation from a mechanicalstandpoint are greater than those found in the machine of the Minettpatent. More specifically the purpose of the present invention is toprovide an improved curved hook needle machine with a loop taker typeshuttle and an internally supported thread case in which the shuttle issecured rigidly to an elongated rearwardly extending shaft provided withbearings of ample size for preventing undue wear when operated at highspeeds.

The machine of the present invention includes generally the sameelements employed in prior machines of the same type but, in accordancewith the objects above noted, the shaft to which the shuttle is securedhas aligned radial bearings, the axis of which is inclined at such anangle to the horizontal, and has a thrust bearing at such a lengthwiseposition that the plane defined by the shuttle intersects the circularpath of the needle and, preferably, passes between the axis about whichthe needle oscillates and the point on the work at which the needleoperates. By locating the shuttle in a plane thus defined, no specialprecautions are required in effective shedding of each needle loop fromthe shuttle beak although the shuttle does act in carrying each needleloop about the enclosed thread case to draw the thread away from thehooked end of the needle in a manner which is detrimental to easydisengagement of the thread from the needle hook.

A further object of the invention is to provide means which will allowthe use in a loop taker type of machine of a shuttle located above ahorizontal work support'and disposed in the position indicated, while atthe same time; any inherent difiiculties resulting from this shuttleloca tion in disengaging the thread from the hook of the needleareovercome. In carrying out. this latter object, means separate fromthe shuttle is provided for lifting each loop of thread from the needlehook in a manner to avoid damaging the thread and to insuredisengagement of the thread from the needle hook accurately at theproper time. Inits illustrated form the loop retracting means consistsof an arm cooperating with a loop spreader after the spreader has openedeach needle loop for the reception of the loop taker. The loopretracting arm also assists in moving the thread in a spread loop towardthe open throat of the loop taker after the loop is disengaged from theneedle so that the loop will be amply spread for passage about thethread case. After the loop is disengaged from the needle the loopretracting arm is actuated in a reverse direction to avoid interferencewith the loop as it passes about the thread case and the retracting armalso is actuated transversely to the loop so that the loop is left freefor movement about the locking thread supply case.

For retaining the thread case against rotation with the shuttleaccording to this feature of the invention, the rearwardly extendingshuttle shaft is constructed in the form of a hollow tube through whichpasses a stationary shaft slidingly supporting a thread case engagingmember, all of the moving parts being located inside an oil retaininghousing for the machine. Such construction results in extreme rigidity,great durability and freedom from vibration or erratic action undernormal operating conditions. Also it is possible to clamp the retainershaft where it projects from the tubular loop taker shaft. Preferably,the thread case engaging member consists of one of a pair of fingersslidingly mounted in the stationary shaft and actuated alternatelytoward and from engagementwith cooperating recesses in the lockingthread case.

These and other features of the invention as hereinafter described andclaimed will more clearly be understood from the following descriptiontaken in connection withthe accompanying drawings, in which:

Fig. l is a fragmentary perspective view of the upper portion of a shoesewing machine head embodying the features of the present invention;

Fig. 2 is a view in left side elevation on an enlarged scale, partly insection and broken away of the shuttle, thread case and some associatedparts of the machine;

Fig. 3 is a view in right side elevation of the loop spreader, the loopretracting arm, and the hook needle of the machine showing theirrelative positions after each loop has been drawn through the work bythe needle;

Fig. 4 is a similar view of the same parts showing their positions afterthe loop spreader has acted and the loop taker beak, shown in dot-dashlines, has entered the loop;

Fig. 5 is a similar view of the same parts, showing the position oftheloop retracting arm while lifting the thread fromthe needle hook;

Fig. 6 is a similar view of the same parts after the needle-loop hasbeen disengaged from the loop spreader and the thread retracting arm;

Fig. 7 is a plan sectional view on an enlarged scale of parts containedin an oil retaining housing of the machine,- certain parts having beenbroken away to illustrate more clearly the underlying construction;

Fig. 8 is a diagrammatic view of the path formed by the. thread engagingend of the loop retracting arm as seen from above, the path of theneedle being shown in broken line;

Fig. 9 is a view in right side elevation of the loop spreader and loopretracting arm together with their actuating mechanisms;

Fig. 10 is a plan view of a portion of theloop retracting armactuatiugmechanism; and

Fig. 11 is a'tim'e chartshowing the relative movements ofithe' loop'spreader, the loop retracting arm, and the locking thread case retainingmembers, plotted against rotation of: the sewing shaft in degrees endingat the machine it is engaged loosely by a driver.

stoppedpositionof the shaft after the final stitch in a seam has beencompleted.

The illustrated machine is a shoe outsole stitching machine which,except as hereinafter described, is the same as that disclosed in theabove-noted patent to Gouldbournet al., to whichreference may be had fora more complete understanding of the manner of constructionand modeofoperation. As in the machine of that.

patent the present machine makes use of a curved hook needle 2 and acurved awl 4 which oscillate about a horizontal stud 6 having a fixedaxis 8 in a circular path v9 (Figs. 3 to 6 inclusive), theneedle and awlalways remaining in the same fixed path. The work, indicated at 10, issecured in the machineduring sewing operations cluding a rotary take-up16 (Fig. 1) which gives up and takes up thread operated upon duringsewing; The work support and presser foot make their idle returnmovement along the line of work feed while the awl engages the work andholds it against backward movement with the work support and presserfoot.

In the machine of the Gouldbourn et al. patent, the

shuttle is mounted in a raceway above the work support for easy accessand visibility and rotates only twice per stitch forming cycle at analternately accelerated and decelerated rate of speed. To rotate theshuttle of that The Gouldbourn et al. shuttle also is of the type whichpasses through each loop of needle thread along with a thread casecontained therein and is disposed with its loop entering beak rotatingin a path defining a plane approximately intersecting the work at thepoint of needle and awl operation substantially perpendicular to thework so that after engaging each loop of needle thread with the shuttleof the patented machine the loop is drawn away from the work in aperpendicular direction. Such arrangement of the shuttle is of advantagesince it produces an elevating reaction on the work at right angles tothe clamping surface of the presser foot so that the pull on the needleloop is adequately resisted by the presser foot. Also the looppassesbodily about the shuttle in the simplest possible manner between theloosely engaged shuttle and driver so that entanglement with other partsof the machine are avoided.

Unlike the machine of the Gouldbourn et al. patent, however, the presentmachine is provided with a rotary shuttleof the loop taker type securedrigidly to a supporting-shaft making three complete rotations at uniformspeed to each sewing cycle ofthe other stitch forming devices in themachine:

With' ashuttle of the loop taker type such as disclosed in the Minettpatent in which each needle loop passes, only about the locking threadcase contained in the shuttle, both sidesof the needle loop extend fromthe open end of the shuttle at the rear thereof. In this latter machine,the beak of the shuttle rotates in a circular path defining'a planeextending'clear of the needle path and disposedin" such position thatthe loop of needlethread asit is being'carried about the thread case isforced to intersect the circular path of the needle, both sides of theloop lying along the same fiat end wall of the thread case where itsmovements may be obstructed by other parts of the machine, such as theneedle and needle guide. For this reason there is no natural tendencyfor the thread inthe loop to clear the rearward end of the shuttle andaccordingly; the shuttle of .that patent is provided with a helicalribrunning. from, its open throat. to; its rearward'end; Duringrotationof the shuttle. after the loop is carried into its throat, the helicalrib prevents the thread from being wound up with the shuttle, the

rib fending the thread rearwardly until it swings clear of thethreadcase end wall. This rib projects radially from thecircumferentialwall'of the shuttle a substantial distance in a manner torequire undesirable compromise in the motions of other parts of themachine, including those of the loop spreader.

The shuttle of the illustrated machine comprises a hollow cup-shapedassembly providing within it an enclosure for a supply of lockingthread. Referring to' Fig. 2 of the drawings, the shuttle is formed asan integral rigidly secured enlargement of a rearwardly inclined hollowshaft 18 journaled in a downwardly and forwardly extending sleeve 20 ofa main oil retaining housing 22 which is fixed 'on the head casting inplace of the cover referred to in the prior Gouldbourn et al. patent bythe numeral 5. The shuttle also has formed thereon a loop-entering beak24 (Figs. 4 and 5) and a counterbore along the internal surface of theenlargement. The counterbore together with an adjacent face of aretaining place 26 (Fig. 2) secured to the enlargement, provides arectangular groove or raceway 28 in which is received a peripheralflange 30 formed on a locking thread supply case 32 of hollowcylindrical form closed at one end, which case is rotatably mountedinside the shuttle thereby.

The locking thread case has a central split sleeve 34 extendingforwardly, on which a bobbin 36 turns freely, being retained thereon bya rim on the forward end of the sleeve. As with the peripheral flange onthe locking thread case in the Minett patent, the present thread case iscut away leaving one end of the flange forming a thread guiding shoulder(not shown herein), and the thread case is restrained from rotation withthe shuttle by retaining means arranged out of the area of operationoccupied by the other stitch forming devices, as will be describedhereinafter.

For rotating the shuttle, the hollow shaft 18 is driven by a gear 38fixed to the rear end of the hollow shaft, which gear meshes at a ratioof 2 to 3 with a larger gear 40 fixed on a forward end of anintermediate shaft 42 journaled in bearings provided in the housing 22.The rearward end of the intermediate shaft carries a gear 44 whichmeshes at a ratio of 1 to 2 with a larger gear 46 fixed on a mainvertical sewing shaft 48 which corresponds with and is driven in thesame manner as the shaft referred to as 33 in the prior Gouldbourn eta]. patent, at the rate of one revolution per cycle of the machine, allof the stitch forming devices including the needle being actuated by themain sewing shaft. The shuttle therefore, is constantly rotated at aspeed of three revolutions per cycle of the stitch forming devices inthe machine. It will be noted that as the shuttle is integrallyconnected to the hollow shaft 18 a loop of thread cannot be passed overthe shuttle, but is passed only around the locking thread case with thesides of the loop both running across the forward end of the shuttle Theangle and lengthwise position of the shuttle shaft 18 are such that,with the shuttle rotating in a counterclockwise direction as seen fromthe front of the machine,

its front face and a plane defined by the rotary path of its beak, isinclined downwardly and forwardly toward the work 10, the plane of theshuttle beak being illustrated by the dot-dash lines of Figs. 4 and 5.When the needle has descended through the work and is withdrawnupwardly, a loop of thread, indicated at 49 in Fig. 5, is drawn throughthe work by the hook of the needle. A thread lifter, corresponding tothe thread lifter referred to as 163 in the prior Gouldbourn et al.patent engages the right leg of the loop on the needle lifting itforwardly and upwardly, the thread being still retained in the hook. ofthe needle, so that the shuttle beak during oneof its rotati ons.canenter the loop, The loop is then taken by the shuttle beak in itsrotationand the portion of the loop which is on the inner side of theshuttle beak is caught by the thread guiding shoulder of the stationarylocking thread case. At about this point in the cycle, the. threadleavesthe needle hook. Continued rotation of the shuttle causes theinner left side of the thread loop caught by the locking thread case tobe passed along the guiding shoulder behind the locking thread casewhile the outer right side of the thread loop'passes across the front ofthe thread case, thus giving the loop a half twist in a clockwisedirection as seen from above. As the rotation of the shuttle iscompleted the thread is shed from the thread case and the shuttle beamand is drawn downwardly clear of the shuttle by the take-up.

To restrain the locking thread case 32 from rotation with the shuttle,yet at the same time to allow the thread loop to pass behind it, therear face of the locking thread 'case is provided with two notches 50and 51 at substantially diametric points, which are engaged by tworeciprocating locking thread case retaining fingers 52 and 54 slidinglymounted for axial movement toward and from the thread case. Thesefingers are of truncated V-shape in cross-section and are secured to theforwardends of two rods 56 and 58 which slide in' two holes in a headed,stationary shaft 60. The shaft 60 extends along the inside of the hollowshaft 18 for the shuttle. The rear end of each rod is reduced indiameter forming a shoulder, against which shouldersabut springs 62 and64 assembled on reduced ends of the rods.

To enable each needle loop to pass between the fingers 52 and 54 and thelocking thread case, the rearward ends of the rods 56 and 58 passloosely through a pair of blocks 66 and 68 held in engagement with thesprings 62 and 64 on the rods by check nuts 70. Each block has formedupon it, a laterally projecting trunnion 72. The trunnions engage theforward end portions of links 74 and 76 as pivots, the rear ends of saidlinks being pivotally connected to depending arms of bell crank levers78 and 80. The bell crank levers are pivoted on parallel shafts '82 and84 mounted with their ends in a bracket 86 fixed in the housing 22and-in the housing itself. The other horizontal arms of the bell cranklevers 78 and carry cam follower rolls 88 and 90 which engage peripheraltracks in a cam 92, secured to the vertical sewing shaft 48. The camtracks are so shaped and arranged that the fingers 52 and 54 arewithdrawn alternately from engagement with the locking thread case toallow the passage of the needle thread loop behind the locking threadcase, the first finger reengaging immediately after the loop has passedand before the second.

finger disengages in the manner indicated in Fig. 11. The shape of thefingers and character of resiliency provided by the springs 54 and 56allow the fingers to become disengaged from the locking thread case inthe event that the locking thread case becomes jammed in the shuttle,thus rendering breakage of machine parts unlikely.

The thread case retainer shaft 60 is secured in place at its upper endwithin a clamp 94 fixed to the housing 22. To steady the lower end ofthe shaft 60 it is loosely surrounded by a bushing 96 secured within thehollow shaft 18, the bushing rotating with the shaft 18.

The hollow shuttle shaft 18 is journalled in a complete and effectivebearing system within the sleeve 20, which bearing system is of adequatesize and durability for long continued service. The bearing system forthis shaft comprises radial and thrust ball-bearings 98 and 100 for theupper end of the shaft and a radial hearing or bushing 102 in the sleeveat the lower end of the shaft 18. The radial bearings have their axisinclined upwardly from the horizontal to the rear of the machine forpurposes to be set forth.

It will be appreciated that, since each stitch is formed during everythird rotation of the shuttle, it is only necessary for the lockingthread caseretaining fingers to operate during that] particularrotation, and, that ,both fingers may be held in engagement with thelocking thread case at all other times. This object is achieved byactuating the fingers from the cam 92 on the vertical shaft by theshuttle.

ABwhich rotates only .once to everythree rotationsofthe vshuttleand.thus unnecessary movement and consequent wearof the fingers and lockingthread case are obviated.

It will also ,be appreciated that the shuttle of the illustrativemachine is integral with a relatively long rearwardly inclined shaftjournalledin .a complete bearing system and running at ,aconstantrelative speed as con- Qtrasted with the shuttle of the prior Gouldbournet al. patent, the,.latter bearing system being of necessity incompleteto allowthe passage of the needle thread loop toward and from theshuttle. The illustrated bearing system therefore is of definiteadvantage in reducing wear and maintenance costs, and in increasing thereliability in operation of the machine .as well as improvinglubrication .of theparts.

For the purposeof spreadingand holding open the loop .of thread drawn upthrough the work by the needle 2 so .that .theshuttle beak .may enterthe .loop, the illustrative machine isprovided with a needleloopspreader or thread lifter 104 .corresponding with the thread lifterreferred to in the prior Gouldbourn et al. patent at 163 and actuated insubstantially ,the .same manner by means of alink 106, a lever 108 and acam 110 (Fig. 9) fixed on the vertical shaft 48.

In the machine of the Gouldbourn et al. patent the shuttle is mounted torotate on .a horizontal axis with its loop entering beak rotating in aplane intersecting the point of needle operation on the work so that theshuttle beak engages each loop ofneedle thread and draws itsubstantially at right angles upwardly from the point of needleoperation. The upward pull of the loop as it is drawn by .the shuttle isresisted effectively by the clamping .action of the presserfoot on thework close to the point -of .needle operation. In drawing the loopupwardly the after moving upwardly to enter a needle loop, movesforwardly, the ,front of the shuttle beinginclined forwardly toward the.work. While moving forwardly and upwardly as the beak enters the needleloop, the thread slides along the edge of the beak rearwardly in .amanner more or less compensating for the forward component ofbeakmovement so that the net result of the upward movement in the shuttlebeak is to draw the needle loop at right angles to the work from thepoint of needle operation as in the Gouldbourn 'et al. machine. Inadditionto this advantage, the present shuttle having its forwardendopen and facing toward the point of'needle operations instead ofrearwardly away from it as in the machine of the Minett patent, affordsa much smoother movement of the needle loop as it passes about thelocking thread case. A particular benefit is obtained as the rightorouter side of the needle .loop is drawn upwardly Instead of tending towind about the vshuttle as thens'huttle rotates, as with the Minettshuttle, it is drawnatanangle to. the plane of the {shuttle so that itquickly passes across the front of the shuttle without the necessity offorminga thick radially projecting diagonal rib for this purpose asrequired by the Minett machine. Accordingly, the thickness of thecircumferential shuttle side wall may be substantially reduced providinggreater space for the other stitch forming devices about the sewingpoint.

The'construction-and arrangement of .tl1e 'loop taker shuttle, ,thusset'forth, retains all of the thread-hantdling advantages of the trueshuttle arrangement, dis- At high speeds 'the-mechanical advantages ofthe loop taker type shutclosed inthe Gouldbourn et al. patent.

tie .in the Minettpatent are secured, but, without .the disadvantages ofthe Minett shuttle, so far asrequirements of exposed gear drive,relatively thin shuttle supporting raceway and radially projecting loopdeflecting rib formation on the outer surface are concerned. Thebushings for the present shuttle and thread case retaining members havereadily accessible communicating passages to the oil retaining housing22 for the machine,

the inclination of the sleeve 20 in which the shaft rotates providingnatural seepage of oil in the casing to. all of the wearing partswithout endangering overthrow on the work operated upon.

While avoiding a limiting requirement in the used the Minett shuttle,the shuttle of the illustrated machine is somewhat at a disadvantage indisengaging the thread from the hook of the needle, and accordingly,additional loop retracting means is provided for this purpose. Withoutthe retracting means, the needle thread would become stranded or injuredon the barbed hook of the needle as the loop is drawn upwardly by theshuttle.

For the purpose of disengaging the thread from the hook of the needle 2in a manner to prevent stranding, breaking or other injury to thethread, the illustrated machine is also provided with a loop retractingarm 112 (see Fig. 9) the loop engaging portion of which is of similarstructure to the loop spreader 104,'but which moves rearwardly in asubstantially horizontal path into engagement with the thread along thelength extending between the shuttle beak and the hook of the needle tolift the loop of thread out of the needle hook as the shuttle beak 24raises the loop.

To actuate the loop retracting arm 112 it is formed, above its loopengaging end, with a hole 114 through which passes a pin 116 forming apivot for its oscillation transversely toward and from the spread needleloop along the line of work feed. The pin 116 is secured to a swingingcarrier 118 which in turn is pivoted for forward and rearwardoscillation on coaxial pivots 120 carried by a bracket 122 attached to aforward extension of the housing 22. The swinging carrier 118 has formedthereon a rearwardly extending arm to which is pivotally connected at124 one end of a link 126. The other end of the link 126 is pivotallyconnected to an upwardly extending arm of a bell crank 1ever 128 pivotedon :a

. lateral fulcrum 139 supported in .a portion of the housing 22, nearthe vertical cam shaft 48. A rearwardly extending arm of the bell cranklever 128 has a cam roll 132 engaging a cam track 134 in the cam 110.The connections described cause the loop retracting arm 112 to oscillatein a direction toward and from the needle.

In order to avoid unintentional engagement with the thread in the needleloop by the retracting arm 112 after the loop spreader 104 first engagesthe loop, the retracting arm is disposed slightly to the right of theneedle when'not performing its loop retracting OPEl'flTHHLxbUl. movestransversely to the left across a plane passing through the circularpath of the needle, just above the needle hook. To impart transversemovement to the loop retracting arm it extends upwardly beyond its pivotpin 1-16 and is constructed with a socket for oneend of a ball endedlink 135, the other end of which is similarly connected .to an arm of asmall bell'crank lever136 which is pivoted on a vertical fulcrum 138projecting upwardly from the bracket 122. t A laterally extending arm ofthe bell crank lever 136 is pivotally connected -to one end of ahorizontal link 140, the other end of which is pivoted to a cam lever142 (Figs. 7 and 9). The cam lever 142 is fulcrumed on a vertical shaft144 fixed in the housing 22. The cam lever 142 carries a rolll45 (Fig.-7) which rides in a track 146 formed in ,the, upper face ofjthe camlll).

Referring to'j'Fig. 11 the resultant. movement; of .the threadretracting arm when the two motions justgdescribed are combined whenseen from above is substantially trapezoidal in form as shown in Fig. 8.During a portion of the time during which the loop of thread is beingdrawn up through the work by the needle, the spreader 104 is stationarybehind the needle point and the loop retracting arm 112 is stationaryabove but slightly to the right of the loop so that the loop is notobstructed when lifted by the spreader as shown in Fig. 3. As the needlecontinues its upward movement along its arcuate path the loop is carriedrearwardly and the spreader m4 commences to swing forwardly and upwardlytaking with it the right side of the loop, looking from the front of themachine, to open the loop for the entry of the shuttle beak.

In Fig. 4 the beak is shown as it starts to lift the loop. Theretracting arm 112 by this time has commenced to move rearwardly and tothe left of the machine across the plane of the needle path, andcontinu'es in that direction until it engages the loop and lifts itclear of the hook of the needle, as shown in Fig. 5. The shuttle beak24, in the meantime, is swinging upward, forwardly and to the left, aportion of the loop sliding along the beak into the throat of theshuttle. The retracting arm then moves forwardly with substantially noright transverse movement, giving up the thread only as the loop istaken up by the shuttle.

It will be appreciated that during the time the thread is engaged withthe retracting arm 112, as shown in Fig. 5, it will be deflected lessand less by the arm as the arm moves forwardly until the thread reachesa straightened position, at which time, the retracting arm becomesdisengaged therefrom. It will also be appreciated that at that sameinstant the retracting arm becomes disengaged from the thread, therewill be no twanging or snapping action of the thread laterally off theretracting arm. To assist in this purpose'the return transverse movementof the retracting arm is delayed until it has moved sutficientlyforwardly to become completely disengaged from the thread. As the needleloop reaches a position where it is free of the shuttle, the retractingarm returns to aleft transverse position while completing its forwardmovement and commences its rearward movement, continuing it until theretracting arm returns to the position shown in Fig. 3. It will berecognized that the action of the loop retracting arm 112 in lifting theloop cleanly out of the needle hook is likely to reduce sliding,stranding or other injury to the thread on the sharpened edges of theneedle barb. I

The nature and scope of the invention having been indicated and aparticular embodiment having been described, what is claimed is:

1. In a shoe sewing machine, a curved hook needle, a stud having a fixedaxis about which the needle operates in a circular path, a hollowcup-shaped shuttle having a needle loop entering beak and an internalraceway, and a thread case rotatably mounted in the raceway, thecombination with an elongated shaft to which the shuttle is rigidlysecured and an oil retaining housing for the machine including adownwardly and forwardly inclined sleeve communicating with the housing,in which sleeve the shuttle shaft is rotatably mounted with its axissimilarly inclined, the shaft being disposed in a lengthwise positionwhere the plane defined by the shuttle beak intersects the circular pathof the needle.

2. In a shoe sewing machine, a curved hook needle, a stud having a fixedaxis about which the needle oscillates in a circular path, a hollowcup-shaped shuttle having a needle loop entering beak and an internalraceway, and a thread case rotatably mounted in the raceway, thecombination with a shaft to which the shuttle is rigidly secured mountedto rotate in the machine at both an angle and a lengthwise position inwhich the plane defined by the shuttle beak intersects the circular pathof the needle, and means passing lengthwise through the shuttlesupporting shaft for retaining the thread case against rotation with theshuttle during sewing operations.

3. In a shoe sewing machine, a curved hook needle, a

stud having a fixed axis about which the needle oscillates in a circularpath, a hollow cup-shaped shuttle having a needle loop entering beak andan internal raceway, and a thread case rotatably mounted in the raceway,the combination with a shaft to which the shuttle is rigidly securedmounted to rotate in the machine at both an angle and a lengthwiseposition in which the plane defined by the shuttle beak intersects thecircular path of the needle, and means passing lengthwise through theshuttle support-' ing shaft for retaining the thread case againstrotation with the shuttle during sewing operations and comprising astationary shaft surrounded by the shuttle shaft and a thread caseengaging member slidingly mounted for axial movement toward and from thethread case within the stationary shaft.

4. In a shoe sewing machine, a curved hook needle, a stud having a fixedaxis about which the needle operates in a circular path, a hollowcup-shaped shuttle having a needle loop entering beak and an internalraceway, and a thread case rotatably mounted in the raceway, thecombination with an elongated shaft to which the shuttle is rigidlysecured mounted for rotation on an axis extending downwardly andforwardly of the machine and disposed v in a'lengthwise position inwhich the plane defined by the shuttle beak intersects the circular pathof the needle, and means separate from the shuttle and mounted formovement in proximity to the position of a loop of needle thread as itextends between the shuttle and the needle for lifting each loop ofthread carried through the work from the hook of the needle.

5. In a shoe sewing machine a curved hook needle, a stud having a fixedaxis about which the needle oscillates in a circular path, a hollowcup-shaped shuttle having an internal raceway, and a thread caserotatably mounted in the raceway, the combination with an elongatedshaft to which the shuttle is rigidly secured, bearings for the shaft inwhich the shaft is rotatable about an axis extending downwardly andforwardly of the machine, a loop spreader for opening each loop ofneedle thread for entry of the shuttle and a loop retracting arm actingafter the loop spreader has opened a needle loop for entry of theshuttle to engage the thread in the loop between the shuttle and theneedle for lifting it from the needle hook.

6. In a shoe sewing machine, a main sewing shaft, a curved hook needleactuated by the main sewing shaft, a stud having a fixed axis aboutwhich the needle oscillates in a circular path, a hollow cup-shapedrotary shuttle having a loop entering beak and an internal raceway, athread case rotatably mounted in the raceway, a clamp for securing thework in a substantially horizontal position during sewing operations,and a shaft to which the shuttle'is rigidly secured driven from thesewing shaft, the combination with a bearing system for the shuttleshaft having alined radial bearings, the axis of which is inclined atan' angle to the horizontal, and having a thrust bearing for retainingthe shuttle in a position lengthwise of the shuttle shaft axis in whicha plane defined by its peak intersects the circular path of the needle.

7. In a shoe sewing machine, a main sewing shaft, a curved hook needleactuated by the main sewing shaft, a stud having a fixed axis aboutwhich the needle oscillates in a circular path, a hollow cup-shapedrotary shuttle havinga loop entering beak and an internal raceway, athread case rotatably mounted in the raceway, a clamp for securing thework in a substantially horizontal position during sewing operations,and a shaft to which the shuttle is rigidly secured driven from thesewing shaft, the combination with a bearing system .for the shuttleshaft having alined radial bearings, the axis of which is inclined at anangle to the horizontal, and having a thrust bearing for retaining theshuttle in a position lengthwise of the shuttle shaft axis in which aplane defined by its beak intersects the circular path of the needlebetween the needle axis and the point of needle operation on the work,

11 the front of the shuttle being inclined'forwardly toward; the'work.

8'. In a shoe sewing machine, a main sewing shaft, a curvedfhook needleactuated by the main sewing shaft, a stud'having a fixed axis aboutwhich the needle oscillates in a circular path, a hollowcup-shapedrotary shuttle having a loop entering beak and an internalraceway, a thread case rotatably mounted in the raceway,. a clampforsecuring the work in a substantially horizontali position during sewingoperations, and a shaft to which the shuttle is rigidly secured'drivenfrom the sewing shaft, the combination with a bearing. system for theshuttle shaft'having alined radial bearings, the axis of which isinclined at an angle to the horizontal, and havinga thrust bearing forretaining the shuttle in a position lengthwise of the shuttle shaft axisin which a plane defined'by its beak intersects the. circular path ofthe needle, and means separate from the shuttle for liftingeach loop ofthread from'the heck of the needle.

9. In a shoe sewing machine, a main sewing shaft, 21

curved'hook needle actuated by the main sewing shaft, astud'having afixed axis about which the needle oscillates ina circular path, a hollowcup-shaped rotary shuttle having a loop entering beak and an internalraceway, a thread case rotatably mounted in the raceway, a clamp forsecuring the work in a substantially horizontal position during sewingoperations, and a shaft to which the shuttle is rigidly secured drivenfrom the sewing shaft, the combination with a bearing system for theshuttle shaft'having alined radial bearings, the axis of which isinclined at an angle to the horizontal, and having a thrust bearing forretaining the shuttle in a position lengthwise of the shuttle shaft axisin which a plane defined by its beak intersects the circular path of theneedle, and means separate from the shuttle for lifting each loopofthread. fromthe hook of the needle, comprising a retracting arm mountedfor movement in proximity to the position of a loop of needle thread asit extends between the shuttle and the needle for engaging the needleloop and liftingit. from the hook of the needle.

10; In a shoe sewing machine, a main sewing shaft, 21 curved-hook needleactuated by the. main sewing shaft, a stud having a fixed axis'aboutwhich the needle oscillates in-a circular path, a hollow cup-shapedrotary shuttle having ailoop enteringbeak and an internal raceway, a.thread case rotatably mounted in the raceway, a clamp. for securing thework in a substantially horizontalpositionduring sewing operations, anda shaft to.which the shuttle is rigidly secured driven from the sewing,shaft, the combination with a bearing system for the shuttleshaft'having alined radial bearings, the axis of'which iS inclined atanangle to the horizontal, and having a thrust bearing for retaining theshuttle in a position lengthwise, of the shuttle shaft axis in which;aplane definedby its beak intersects the circular path of the needle, aloop spreader for'opening each loop of'needle'thread'for entry ofthe-shuttle beakand a loop retracting arm mounted" for movement inproximity to the loop ofneedle'thread extending between the shuttle andthe needle for engaging the loop and lifting it from the hook of theneedle.

11. In a shoe sewing machine, a main sewing shaft, a curvedhook. needleactuatedby the main sewing shaft, a stud having aiixed axis about whichthe needleioscillates in a circular path, a hollow cup-shaped rotaryshuttle having a loop entering beak and'an internal raceway, a threadcase rotatably mounted inthe raceway, a clamp for securing the Work in asubstantially horizontal p osi-, tion during sewing operations, and ashaftto whichthe shuttle is rigidly secured driven from the sewingshaft,

the combination with a bearing system for the shuttle;

shaft'having alined radial bearings, the axis of which is inclined at anangle to the horizontal, and having a thrust bearing for retaining theshuttle in a position lengthwise of the shuttle shaft axis in which aplane defined by its beak intersects the circular path of the needle,means' separate from the shuttle for lifting each loop of thread carriedthrough the work by the needle from its hook comprisinga retracting armmounted for movement'in proximity to the loop of needle thread extendingbetween. the shuttle and the needle and a carrier on which theretracting arm is movable transversely from the needle loop.

12'. In a shoe sewing machine, a main sewing shaft, a curved hook needleactuated by the main sewing shaft; a stud'havinga fixed axis about whichthe needle oscillates in.a circular path, a hollow cup-shaped rotaryshuttle having a loop entering beak and an internal raceway, a threadcase rotatably mounted in the raceway, a clamp for securing the work ina substantially horizontalposi: tion during sewing operations, and ashaft. to which the, shuttle is rigidly secured driven from the sewingshaft, the combination with a bearing system for, the shuttle. shafthaving alined radial bearings, the axis of which.is inclined at an angleto the horizontal, and having a thrust. bearing for retaining theshuttle in a position lengthwise of the shuttle shaft axis in which aplane defined by its beak intersects the circular path of theneedle,means separate from the shuttle for lifting each loop ofthread carriedthrough the work by the. needle from its book comprising a retractingarm mounted for movement in proximity to the loop-of needle threadextending between the shuttle and the needle, a carrier on which theretracting'armis movable transversely from the needle loop, and"mechanisms for actuating the retracting arm and carrier. tomove the'armtransversely to a position Within'the loop of thrcadengaging the needlebefore moving it in a direction to lift the thread from the needle hook.

13. In' a shoe sewing machine, a curved hook needle, a-shuttle and aloop spreader for opening each loop of thread carried by the needle forentry of the shuttle, the combination with a loop retracting arm mountedfor movement in proximity to the thread extending between the shuttleand'the needle .to lift the thread from the hook ofthe needle after theloop spreader has opened it.

14. In a shoe machine, a curved hook needle, a stud having a fixed'axisabout which the, needle operates in a. circular'path; a hollowcup-shaped shuttle having a loop entering beak and an internal raceway,a threadcase rotatably mounted in the raceway and a clamp for securingthe work in a horizontal position during sewing operations, the:combination with an elongated shaft to whichth'e shuttle is'rigidlysecured mounted for rotation about an axisextending downwardly andforwardly of the machine, and disposed in alengthwise position, in whicha plane defined" by the shuttle beakintersectsthe circular path ofthe=needle;

References Cited in the file of this patent UNITED STATES PATENTS533,639 Eppler ...Feb. 5; 1895. 1,142,391 Ballard June 8, 19151,688,056, Reed Oct. 16,1928: 1,794,255 Stephenson Feb. 24, 19312,056,670 Gouldbourn et al Oct. 6, 1936 2,178,543 Rubel et al. Nov. 7,1939 2,447,987 Parry Aug. 24, 1948l

